Wager-based gaming in the United States is divided into Class I, Class II, and Class III games. Class I games generally include social games played for minimal prizes, or traditional ceremonial games. Class II games generally include bingo and bingo-like games (as well as central determination games). Class III games generally include any games that are not Class I or Class II games, such as games of chance typically offered in non-Indian, state-regulated casinos.
For a play of a traditional Class II bingo game, each player purchases one or more bingo cards that bear multiple bingo numbers of a set of a plurality of bingo numbers. The bingo numbers of the set are then sequentially drawn at random (e.g., selected via a random number generator). If a drawn bingo number matches a bingo number on a player's bingo card, that bingo number is marked (which is often referred to as “daubing”) on the player's bingo card. The draw continues until the marks on one of the player's bingo cards form a game-winning pattern (which is sometimes called a game-ending pattern). At that point, the play of the Class II bingo game ends, and the player whose marked bingo card forms the game-winning pattern is provided an award.
Some Class II bingo games also include one or more interim patterns. If the marks on a player's bingo card form an interim pattern, the player wins an interim award. Unlike a game-winning pattern match, an interim pattern match does not end the bingo number draw. Some Class II bingo games require an interim pattern to be marked within a particular quantity of bingo number draws (e.g., within the first five or ten bingo number draws). Class II bingo systems typically rank interim patterns from highest to lowest priority (e.g., highest to lowest associated interim award). If multiple interim patterns are marked on a single bingo card, the Class II bingo system usually provides the interim award for the highest priority marked interim pattern and ignores the other (lower priority) marked interim patterns.